DB Sanity performs checks on a database for verifying data consistency and correctness of aplication deployments. It is invoked by the command line and creates an HTML report with a summary and listings of faulty database entries.

SpiderDB is a lightweight database schema crawler library developed using Java. It is a simple library that can be used to Crawler the underlying schema of a database and return POJO objects, which makes it very easy to use. This library takes care of all the differences among the various database management systems, and makes application code free from the DBMS differences.You keep using same POJOs even if you change the underlying DBMS.

BoneCP is a Java JDBC connection pool implementation that is tuned for high performance by minimizing lock contention to give greater throughput for your applications. It currently beats all known connection pools, including C3P0 and DBCP, as shown on the benchmark section on the site.

Migrations is a tool for managing changes to database schemas. It is an Enterprise tool based on ActiveRecord migrations from Rails. It features multiple schema interactions, runtime substitution of values, script generation, auditing, and much more.

StelsXML is a JDBC type 4 driver that allows you
to perform SQL queries and other JDBC operations
on XML files. It allows you to easily access data
contained in XML documents using the standard SQL
syntax and XPath expressions. The driver is
completely platform-independent. It supports most
keywords of ANSI SQL'92, XPath expressions for
defining tables and columns, inner and outer table
joins, aggregate, numeric, string, conversion, and
user-defined SQL functions.